Research On Spatial Distribution And Pollution Evaluation Of Heavy Metals In Soil Of Jinhua City Based On GIS

With the rapid development of industry, aggravation of the urban pollution and increase in category and quantity of agrochemicals, contaminations that contain heavy metals enter soil through different approaches, resulting in the more serious pollution of heavy metals. Jinhua City is one of the four economic area centers in the Midwest of Zhejiang Province. Therefore, research of the spatial distribution and pollution of heavy metals in the soil is significant to the agricultural development planning and urban land use. The amount of heavy metals in the soil is spatial continuous variable, having the characteristics of regional variables.So it has become more common to apply Geostatistics and GIS to the research of spatial distribution and pollution evaluation of soil heavy metals in recent years.This paper takes Jinhua City as research area, and uses Geostatistics combined with GIS to analyze the spatial variability characteristics, and study the spatial distribution characteristics and pollution situation of heavy metals in the soil of intermediate scale. The following is the main content:(1) This paper studies the theoretical approach of spatial distribution of soil heavy metals which means the theoretical method of Geostatistics.(2) This paper applies Geostatistics to analyze the sample of heavy metal content and study characteristics of the spatial variation structure of it. That has special meaning for soil sample arrangement.(3) The paper researches correlation beteewn spatial region variables among pH,evaluation and eight heavy metals. It also generates spatial distribution map of heavy metals by object-point replacing surface method applying GIS programming and Geostatistics combined with the strong ability of spatial data management and spatial analysis of GIS. It's more intuitionistic in spatial than basing on stating sample in common. And then the paper analyzes the characteristics of spatial distribution.(4)This paper carries out single and integrative pollution evaluation respectively towards the sample data of the amount of the heavy metals in the soil with the integrative index method, and then map according to the evaluation result with GIS technology to visualize the pollution situation of soil heavy metals spatially. The result shows that it is reliable in spatial to map the evaluation result by object-point replacing surface method and it's better to exhibit pollution state of heavy metals in the soil.